You can currently use this calculator to find the expected costs of augmenting an item to a certain level, or calculate how much xp you'll get on average from augmenting a certain item. You can also find out the value you'd get from buying an item that's already augmented. You can put numbers or simple math expressions into the fields, and use 'k' or 'm' shorthands - try putting 15*1.2k to calculate the cost of 15 ingots worth 1200 each.
You can mouse-over some fields to get a clarification of what they need. If you experience any problems, feel free to message Mac15001900 in-game or open an issue on the Github page.

Limitations:

Xp calculations do not take into account leveling up while augmenting, which slightly increases success chances.
For xp calculations, only augments up to +50 are considered.
Remember that in practice you'll usually get less than average xp; this is offset by gaining a lot on rare, high-level augments.